Accessible, self-mounting terminal block



April 12, 1966 P. HUSKA 3,246,283

ACCESSIBLE, SELF-MOUNTING TERMINAL BLOCK Filed Dec. 25, 1963 2 Sheets-Sheet l A as? April 12, 1966 P. HUSKA 3,246,283

ACCESSIBLE, SELF-MOUNTING TERMINAL BLOCK Filed Dec. 23, 1963 2 Sheets-Sheet 2 32 C ZJG. 6.

do INVENTOR.

B404 fl w/A A aswr Patented Apr. 12, 1966 3,246,283 ACCESSIBLE, SELF-MOUNTING TERMINAL BLGCK Paul Huska, Los Angeles, Calif. (1150 18th St, Santa Monica, Calif.) Fiied Dec. 23, 1963. Ser. No. 332,641 6 Claims. (Cl. 339-198) This invention relates to terminal connection of electrical conductors and is particularly concerned with a terminal block that affords improved accessibility to the place of electrical connection and wherein the block is self-mounting upon a rail adapted to receive and hold the same.

Difliculty arises in the adequate provision of-terrninal connections where electrical conductors are joined. Not

only must electrical separation be maintained relative to other conductors, but compactness of construction and accessibility are prime factors to be considered, and in addition it is highly desirable that modification and/ or replacement be easily accomplished. Therefore, it is necessary to isolate conducting elements so as to eliminate danger of short-circuiting; it is highly desirable to dispose the terminal connection so as to be visible and also accessible; and it is highly desirable that the block per se be installable as a modular unit independently of like adjacent units.

An object of this invention is to provide a terminal block unit wherein the electrically conductive parts as well as the terminal conductor ends are electrically isolated by adequate insulation. In the construction hereinafter described there are no weaknesses of design in this connection and no danger of electrical failure.

Another object of this invention is to provide a terminal block unit wherein the axes of the terminal conductor ends are inclined and thereby disposed most advantageously for ease of access. With the structure that I provide, binding posts and/ or clamp type fasteners are avoided, and in accordance with the invention an opening is provided into which the conductor end is simply inserted and after which the structure is tightened.

It is another object of this invention to provide a terminal block wherein the fewest number of parts are required and wherein correct installation of all parts, including particularly the terminal conductor ends, is inherently assured. With the structure hereinafter disclosed, each part involved has its place in the combination and coacts with the other associated parts so as to have but one mode of assembly without requiring additional fasteners, and so as to receive the terminal conductor ends in but the proper manner only. Briefly, the various parts are captured in proper operating position upon assembly, there being positive positioning of parts with guards to assure proper installation of the terminal conductor ends.

It is still another object of this invention to provide a terminal block unit that is self-mounting upon a rail especially provided therefor, all without requirement of additional parts. With the structure that I provide a multiplicity of terminal block units is arranged on a rail as will be described and a keeper at each end of the rail positions the blocks whereby the said blocks are not only positioned on the rail but are simultaneously captured thereon.

The various objects and features of this invention will be fully understood from the following detailed description of the typical form and application thereof, throughout which description reference is made to the accompanying drawings, in which:

FIG. 1 is a perspective view showing the installation of a multiplicity of terminal blocks on a rail.

FIGS. 2 and 3 are sectional views through the rail,

FIG. 2 showing the process of positioning the body part and elements carried thereby, and FIG. 3 showing the process of positioning the plate of a mounting means, the parts being moved as indicated by the arrows.

FIG. 4 is a vertical sectional View of a terminal block taken as indicated by line 4-4 on FIG. 1.

FIG. 5 is a vertical sectional view taken as indicated by line 55 on FIG. 1.

FIGS. 6 and 7 are sectional views taken as indicated by lines 66 and 7-7 on FIG. 5.

FIG. 8 is a perspective view of the stirrup-shaped terminal clamp means.

In FIG. 1 of the drawings I have shown a multiplicity of terminal blocks T mounted on a support rail R, there being a keeper K that locates the blocks in position on the rail. It will be readily apparent that any number of terminal blocks T can be arranged adjacently as shown, and that a keeper K or the like can be installed at each end of the row of said blocks (preferably the keeper K as shown). Generally, the invention involves the terminal blocks T each comprising a body A, a bus B, clamp means C,and a mounting means D. Additionally, the invention involves the support rail R which is especially formed to coact with the mounting means D.

The support rail R is the foundation upon which the terminal blocks T are arranged and involves a pair of inwardly disposed flanges 10 and 11 carried in a common plane by upstanding walls 12. It is preferred that the rail R be a single symmetrical part and it is shown as a formed cross-section of one body of material with the walls 12 extending upward from opposite parallel sides of a bottom 13. The bottom 13 is flat and thus the flanges 10 and 11 are parallel with said bottom and are opposed to each other. As a result, the said flanges present a pair of spaced downwardly faced shoulders.

The body A of the terminal block T is formed of an insulating material as shown, preferably by a molding technique. The body A is characterized by its bilateral symmetry except for a single feature which is unique in the self-mounting of the block. Primarily, the body A is a solid part having front and back faces 15 and 16 that are parallel and which are disposed normal to the rail R. That is, the faces 15 and 16 are vertical and extend transverse of the rail R which can be considered as normally horizontal. The body A is considerably wider than the rail R and is chambered and channeled in order to secure the electrically conductive parts. Further, the body A is characterized by its angularity of cross-section whereby opposite sides 17 and 18 face upwardly at an angle. As is shown, the sides 17and 18 are each inclined (on the average) at about 25 so as to extend inwardly from a substantially broad base 19 to a rather narrow top 20. The said angle can vary, it being understood that the broadness of the base 19 will increase with any increase in said angle. Thus, the body A is triangular with a broadened mounting base.

The body A is bilateral in order to accommodate the terminal ends of a pair of opposite conductors with at least one conductor approaching each side 17 and 18. The said conductors have bared ends which enter the terminal block body, there being an opening 21 at each side to pass each conductor into a chamber 22 at each side. Thus, there is a pair of spaced chambers 22 formed within the body A, said chambers being interconnected by a channel 23. In accordance with the invention the chambers 22 and channel 23 are open to the face 16 and are formed into the body A to freely acceptthe clamp means C and bus B. The chamber 22 is a rectangular cavity having a front wall 25 parallel to the face 15, opposed and parallel ,side walls 26 and 27, and top and bottom walls 28 and 29. The channel 23 intersects the chambers 22 whereby the bus B can be carried in said seat at opposite side walls of each chamber. chambers are angularly related the channel is turned or channel so as to pass through the chambers with support at the opposite side walls 26 and 27. As is shown, the channel 23 is normal to the walls 26 and 27 substantially midway between the top and bottom walls 28 and 29.

The bus B is a bar-shaped part that is carried in the channel 23 to span between the two chambers and to Since the bent at the center of the block and is V-shaped. Therefore, the bus B is a V-shaped' bar and which, according to the invention, is of lesser width than the chambers 22. That is, the edges of the bus B are spaced from the wall 25 and also from the back face 16.

The clamp means C involves parts which enter into the chamber 22 to be captured therein, The structure is shown in the assembled condition and wherein the clamp means C involves a stirrup part 30 that is cooperatively related to the bus B with an operating screw 40 acting between said stirrup part and said The stirruppart 30 has a jaw 31 disposed beneath the bus B and it has a head 32 disposed above the bus B. Extending between the jaw 31 and head 32 is one or more legs 33, whereby movement of the head 32 is transmitted to the jaw 31. As shown, the stirrup part 30 is a folded metal tube structure, of one part, wherein a pair of legs 33 project upward from the jaw 31 to straddle and freely pass by the bus B. The two legs 33 then overlap to form the head 32 which is of double thickness and which is threaded to receive the operating screw 40'.

In practice, the tubular part which forms the clamp means C is made of steel and is reinforced with a facer 31' formed of highly conductive metal. The facer 31' is essentially a flat part that overlies the jaw 31 and preferably formed with a concaved conductor-centering face. Said concaved face is established by upwardly swaging the margins of the faoer 31'; and said concaved face being longitudinally knurled or the like as shown. A guard 35 depends from the facer 31' to operate along the wall 26, whereby a conductor end cannot enter under the jaw. The guard 35 is indented at 35' in order to lock onto the jaw 31, there being a tab 36 at the end opposite the guard 35 and which is deflected and/ or turned partially under the jaw 31 to effect a permanent assembly. a

The operating screw 40 is threaded into the head 32 on an axis normal to the jaw 31. Said screw 40 has a head 41 adapted to be turned by a suitable tool, such as by a screwdriver and the head 40 is round and is accessible from the exterior of the body A through an opening 42 in the top 20. The opening 42 is round and enters into the chamber 22 where the screw 40 has a flange 43 engageable with the top wall 28 of the chamber. Thus, the operating screw 40 is made of a length to be captured between said flanged engagement at wall 28 and engagement of the end of said screw with the top of the bus B.

In order to assemble the terminal block T from the parts as above described, suitable clearances are provided so that with the tip of the operating screw 40 entered into the head 32 and with the stirrup part 30 engaged over the bus B, said parts can then be dropped into the chamber and/or chambers 22 and channel 23, and into the alignment shown.

With the parts assembled as above described the mounting means D is applied and which comprises one or more plates 50 of insulating material that fit flush against the back face or faces 16 of the body or bodies A. In carrying out the invention, the bodies A and/or plates 50 are stacked together as may be required; that is, body.

against body or plate against body as may be desired. Thus, the chamber and/or chambers 22 and channel 23 are closed with the stirrup and/or stirrups 30 and with the operating screw and/or screws 40 captured in place with the bus B.

Further, the mounting means D involves the cooperative relationship of the body and plate 50, each of 4 which is characterized by its hooked engagement with the above described rail R. In accordance with the invention the body A is adapted to have hooked engagement with the flange 10, while the plate 50 is adapted to have hooked engagement with the flange 11, or vice versa. Still further, and in order to have positive locking engagement at the two flanges 10 and 11, the plate 50 has keyed engagement with the body A. As is shown, the

body 8 has a keying recess or alternatively and preferably a keyed arrangement of two or more recesses 51 formed in the back face 16, there being correspondingly shaped and placed projections 52 extending from the front face of the plate 50. In accordance with the invention there is an outwardly turned lug 53 at one side of the body A and a seat 54 at the other side. The lug 53 engages under the shoulder formed by flange 10, while the seat 54 rests upon flange 11. Further, there is a shoulder at the seat 54 to engage the inner edge of flange 11. There is an outwardly turned lug 55 at the other side of plate 50 and a seat 56 at the opposite side. The lug 55 engages under the shoulder formed by flange 11, while the seat 56 rests on flange 10. Further, there is a shoulder at the seat '56 to engage the inner edge of flange 11. From FIGS. 2 and 3 of the drawings it will be apparent how the body A and plate 50 are revolved (oppositely) upon installation, and when properly hooked and seated theyare slid into engagement with the projection or projections 52 entering the recess or recesses 51.

As described above, the essential feature of mounting is that the body A has keyed engagement with the mounting plate 50 when respective lugs 53 and 55 are engaged under the flanges of the supporting rail, there being a mounting plate 50 shown between each of the bodies A. It is to be understood, however, that it is not necessary to employ a mounting plate 50 with each and every body A, and therefore both the body A and plate 50 are provided with opposite projections 52 and recesses 51. Thus, the front 15 of one body A is engageable with the back 16 of the next adjacent body A, closing the chambers and channel therein, said bodies being locked against rotation by means of the projection and recess engagement. Further, in accordance with the invention, the projections '52 and recesses 51 are cam shaped so as to have a centering action and as well to have a prying action. The projections 52 and recesses 51 are preferably mating cone shapes, as shown, whereby the inclined formation results in alignment when parts are brought together. Converse- 1y, when the parts are shifted, in any lateral direction, relative to each other, then the inclined formation of the cones results in a cam action that separates the blocks and/or plates.

From the foregoing it will be seen that a multiplicity of terminal blocks T are assembled, each from a body A, a bus B and stirrrup 30 and operating screw 40. The parts are simply placed together with the bus B immovably spanning the chamber or chambers 22. The opening 21 is positioned below the bus B and upon initial assembly the'opening 21 is above the jaw 31. In said initially assembled condition the guard 35, in the nature of a tongue, engages the bottom 29 of the chamber while the flange 43 of the operating screw 40 engages the top 28 of the chamber. Thus, there is positive depression of the clamp means C whereby all obstructions are removed from opening 21, in order to receive the terminal conductor end. However, upon operation and/ or re-use the guard 35 assures that the terminal conductor end cannot be inserted other than between the bus B and jaw 31, even when the stirrup 30 is not fully depressed. Finally, upon insertion of a terminal conductor end in position between the bus B and jaw 31 (see FIGS. 5 and 7) the screw'40 operates as a volume to apply pressure directly between the top of the bus B and head 41. Since the stirrup legs 33 depend equally at either side of the to carry the transverse jaw 31, clamping action is positive without reliance upon any body part of insulating material.

With the parts as disclosed and assembled as above described any number of terminal blocks T can be arranged along the rail R. That is, the bodies A can be stacked in front-to-back relationship and as many mounting plates 50 used as may be advisable. For example, groups of bodies A are arranged directly together and a mounting plate 50 is arranged between a pair of bodies at suitable intervals as determined by said grouping. Thus, the groups of bodies A are locked to the rail R at intervals as may be desired.

Positioning along said rail R is determined by suitable stops or perferably by the keepers K, one at each end of the row of blocks. As is shown, the keeper K is a sheet metal part comprising a plate 60 that extends or spans between the flanges and 11 of the rail. Said plate 60 is fiat and it is provided with a tab 61 that presses flat against the endmost block or mounting plate. In order to secure the keeper K in position the plate 60 has a threaded opening for the reception of a set screw 63 that bites into the bottom 13. Thus, the keepers K are engaged with the endmost terminal blocks T and are set in position by tighening the screws 63.

Having described a typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any modifications or variations that may appear to those skilled in the art and fall within the scope of the following claims.

Having described my invention, I claim:

1. A terminal block including:

(a) a body of insulating material with a chamber formed therein and with an opening into said chamber,

(b) and clamp means in said chamber for engagement with a conductor entered through said opening and comprising, an elongated bus fixedly occupying the chamber, a stirrup-shaped part movably occupying the chamber and with a jaw underlying the bus and with legs at either side of the bus and extending to a head overlying said bus, an elongated facer overlying the jaw and opposed to said bus and with a guard depending therefrom to close the opening when the facer is operated toward said bus, and an operating screw accessible through a second opening in the body to extend between the head and bus to pull the jaw toward said bus and said screw having a flange engaged with the chamber wall to position said screw and cause said screw to retract the jaw and facer from said bus.

2. A terminal block including:

(a) a body of insulating material having a front and a back disposed in spaced parallel planes, a side extending between the front and back, and with a chamber formed in the body and entering the back thereof, and there being an opening into the chamber through said side,

(b) clamp means inserted into the chamber at said back for engagement with a conductor entered through said opening and comprising, an elongated bus fixedly occupying the chamber, a stirrup-shaped part movably occupying the chamber and with a jaw underlying and opposed to the bus and with legs at either side of the bus and extending to a head overlying said bus, and an operating screw accessible through a second opening in the body to extend between the head and bus to pull the jaw toward said bus and said screw having a flange engaged with the chamber wall to position said screw and cause said screw to retract the jaw from said bus,

(c) and a plate of insulating material covering the back of the body and fixedly capturing the bus and movably capturing the stirrup shaped part in said chamber.

3. A terminal block for mounting on a rail having opposite inwardly disposed side flanges, and including:

(a) a body of insulating material having a front and a back disposed transversely of the rail in spaced parallel planes, a side extending between the front and back of the body, a chamber formed in and entering the back of the body, there being an opening into the chamber through said side, and an outwardly disposed hook at one side of the body to engage one of said rail flanges,

(b) clamp means in said chamber for engagement with a conductor entered through said opening and comprising a part with a jaw opposed to a bus and an operating screw extending between the said part and bus to clamp them together with the conductor therebetween,

(c) and mounting means comprisinga plate of insulating material covering the back of the body to capture the clamp means in said chamber, and said plate having an outwardly disposed hook at the other side of the body to engage the other of said rail flanges.

4. A terminal block for mounting on a rail having opposite inwardly disposed side flanges, and including:

(a) a body of insulating material having a front and a back disposed transversely of the rail in spaced parallel planes, a side extending between the front and back of the body, a chamber formed in and entering the back of the body, there being an opening into the chamber through said side, and an outwardly disposed hook at one side of the body to engage one of said rail flanges and a seat to engage the other of said rail flanges,

(b) clamp means in said chamber for engagement with a conductor entered through said opening and comprising a part with a jaw opposed to a bus and an operating screw extending between the said part and bus to clamp them together with the conductor therebetween,

(c) and mounting means comprising a plate of insulating material covering the back of the body to capture the clamp means in said chamber, and said plate having an outwardly disposed hook at the other said of the body to engage the other of said rail flanges and a seat to engage the first mentioned of said rail flanges.

5. A terminal block for mounting on a rail having opposite inwardly disposed side flanges, and including:

(a) a body of insulating material having a front and a back disposed transversely of the rail in spaced parallel planes, a side extending between the front and back of the body and with a keying recess formed in the body and entering said back thereof, a chamber formed in and entering the back of the body, there being an opening into the chamber through said side, and an outwardly disposed hook at one side of the body to engage one of said rail flanges,

(b) clamp means in said chamber for engagement with a conductor entered through said opening and comprising a part with a jaw opposed to a bus and an operating screw extending between the said part and bus to clamp them together with the conductor therebetween,

(c) and mounting means comprising a plate of insulating material covering the back of the body and with a keying projection mated with said recess to capture the clamp means plate on said body, and said plate having an outwardly disposed hook at the other side of the body to engage the other of said rail flanges.

6. A terminal block for mounting on a rail having opposite inwardly disposed side flanges, and including:

(a) a body of insulating material having a front and a back disposed transversely of the rail in spaced parallel planes, a side extending between the front and back of the body and with a keying recess formed in the body and entering said back thereof, a chamber formed in and entering the back of the body,'there being an opening into the chamber through said side, and an outwardly disposed hook at one side of the body to engage one of said rail flanges and a seat to engage the other of said rail flanges,

(b) clamp means in said chamber for engagement with a conductor entered through said opening and comprising a part with a jaw opposed to a bus and an operating screw extending between the said part and bus to clamp them together with the conductor therebetween,

(c) and mounting means comprising a plate of insulating material covering the back of the body and with a keying projection mated with said recess to capture the clamp means plate'on said body, and said plate having an outwardly disposed hook at the other side of the body to engage the other of said rail flanges and a seat to engage the first mentioned of said rail flanges.

References Cited by the Examiner UNITED STATES PATENTS 2,958,068 10/1960 Lipinski 339 -272 2,981,922 4/ 1961 Van 'Valkenburg etal. 339-198 FOREIGN PATENTS 1,063,241 8/ 1959 Germany.

888,403 1/ 1962 Great Britain. 937,008 9/1963 Great Britain.

JOSEPH D. SEERS, Primary Examiner. l 

1. A TERMINAL BLOCK INCLUDING: (A) A BODY OF INSULATING MATERIAL WITH A CHAMBER FORMED THEREIN AND WITH AN OPENING INTO SAID CHAMBER, (B) AND CLAMP MEANS IN SAID CHAMBER FOR ENGAGEMENT WITH A CONDUCTOR ENTERED THROUGH SAID OPENING AND COMPRISING, AN ELONGATED BUS FIXEDLY OCCUPYING THE CHAMBER, A STIRRUP-SHAPED PART MOVABLY OCCUPYING THE CHAMBER AND WITH A JAW UNDERLYING THE BUS AND WITH LEGS AT EITHER SIDE OF THE BUS AND EXTENDING TO A HEAD OVERLYING SAID BUS, AN ELONGATED FACER OVERLYING THE JAW AND OPPOSED TO SAID BUS AND WITH A GUARD DEPENDING THEREFROM TO CLOSE THE OPENING WHEN THE FACER IS OPERATED TOWARD SAID BUS, AND AN OPERATING SCREW ACCESSIBLE THROUGH A SECOND OPENING IN THE BODY TO EXTEND BETWEEN THE HEAD AND BUS TO PULL THE JAW TOWARD SAID BUS AND SAID SCREW HAVING A FLANGE ENGAGED WITH THE CHAMBER WALL TO POSITION SAID SCREW AND CAUSE SAID SCREW TO RETRACT THE JAW AND FACER FROM SAID BUS. 